Date   : Tue, 26 Jul 2005 21:57:32 +0000
From   : Jules Richardson <julesrichardsonuk@...>
Subject: Re: ARM copros, speech cartridges, real timeclocks, etc

On Tue, 2005-07-26 at 23:22 +0200, Johan Heuseveldt wrote:
> > I thought there were no interrupts at present 
> 
> Correct. I didn't say any differently. Did I?

No, that was my fault - I was reading through posts too quickly earlier
so I wasn't sure if I remembered right or not :)

> It was exactly the point that no interrupt system was in use, ever. But
> the Tube ULA /has/ it on board. In the light of more than one CoPro, this
> is, or could be, a valueble addition, as it is present in the hardware,
> ready to be used, though needing new software.

You know, for some reason I think that the ACW (and possibly the ABC3xx
machines) perhaps did make use of an interrupt mechanism. I just can't
remember who told me that and exactly what I was told now though! I've
got the ACW schematics; I'll have to have a look and see. Maybe it
wasn't through the Tube though and wired in via some other way...  (of
course the BBC I/O processor side ran BOS, so it's entirely possible the
Tube-handling code was entirely different to a normal BBC)

cheers

Jules